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981.
To implement the computation of AHP (Analytic Hierarchy Process) automatically, make the implementation independence on the platform, and to convenient the service composition and service computation, this study implemented AHP model as a Web service and stored the evaluation information as XML form. This paper introduces the overall demands of AHP evaluation system firstly, and then presents some key technologies to implement AHP evaluation system, including mainly AHP evaluation index architecture based on XML, the class of AHP model, the Web service encapsulation of AHP, the publication and invocation of AHP and the client application. At last, the system is used to analyze the impact factors of online consumption behavior. 相似文献
982.
“吃+宾”结构是现代汉语中讨论得比较多的问题,本文结合语境理论对其作了综合述评,着重探讨其言内语境;对学者们研究较少的“吃+补”结构着重从语义指向角度分析其言内语境对语义的彰显作用。指出“吃+宾(补)”结构生成发展的深层因素是汉民族的文化、心理、语言习惯。 相似文献
983.
984.
数据流连接操作的执行方式直接影响到查询执行的效率和结果的正确性.在STREAM项目流化方法的基础上,对复杂应用下的数据流滑动窗口连接的准确语义进行了分析和建模,以时间窗口连接的增量维护为例提出了两种改进的基本维护策略,给出了针对元组窗和分组窗的维护方法,讨论了根据参数和环境的不同进行适应性的维护.实验证明了在不同的窗口、流速和选择度下,适应性地选择不同的优化算法会达到最优的处理性能. 相似文献
985.
Silicon is the dominant semiconductor for electronics, but there is now a growing need to integrate such components with optoelectronics for telecommunications and computer interconnections. Silicon-based optical modulators have recently been successfully demonstrated; but because the light modulation mechanisms in silicon are relatively weak, long (for example, several millimetres) devices or sophisticated high-quality-factor resonators have been necessary. Thin quantum-well structures made from III-V semiconductors such as GaAs, InP and their alloys exhibit the much stronger quantum-confined Stark effect (QCSE) mechanism, which allows modulator structures with only micrometres of optical path length. Such III-V materials are unfortunately difficult to integrate with silicon electronic devices. Germanium is routinely integrated with silicon in electronics, but previous silicon-germanium structures have also not shown strong modulation effects. Here we report the discovery of the QCSE, at room temperature, in thin germanium quantum-well structures grown on silicon. The QCSE here has strengths comparable to that in III-V materials. Its clarity and strength are particularly surprising because germanium is an indirect gap semiconductor; such semiconductors often display much weaker optical effects than direct gap materials (such as the III-V materials typically used for optoelectronics). This discovery is very promising for small, high-speed, low-power optical output devices fully compatible with silicon electronics manufacture. 相似文献
986.
LIU Quanjun ZHOU Qin BAI Yunfei GE Qinyu LU Zuhong 《科学通报(英文版)》2005,50(24):2896-2900
A lab-in-a-tube microarray system is developed for sample inspection and signal detection by fabricating a fiat transparent window cap of the Eppendorf tube. The oligonucleotide microarray is immobilized on the inner surface of the cap. A small vessel is placed in an Eppendorf tube for storing hybridization solutions. With the microarray system, the full biochemical processes, including gene fragment amplification, fluorescence labeling, hybridization, and fluorescence detection, have been performed in the sealed tube without opening the cap. The images are obtained from a fluorescence microscope and captured by a CCD, and the data are transported to a computer through the universal serial bus (USB). After noise reduction, signal intensity is determined from hybridization image and the presence of gene fragments is identified. The final data output includes sample information, process steps, and hybridization results. A lab-ina-tube microarray system for detecting ten respiratory viruses at a single detection is designed. High detection throughput and accuracy have been demonstrated with the system. 相似文献
987.
Weidong Sun Xiachen Zhi Zicheng Peng Zhaorong Wang Ningjie Ge Xinhua Zhou 《科学通报(英文版)》1998,43(18):1575-1575
The osmium isotopic ratio of187Os/188Os ranging from 0.126 to 0.127 for the primitive upper mantle (PUM) is obtained according to the correlation between187Os/188Os and Al2O3 of mantle-derived xenoliths and orogenic peridotites, which consists with Allegre and Luck’s ALM value and similar to Yin’s
nuggets uniform reservoir (NUR) value. It shows that the Os isotope ratio is lower than enstatite or ondinary chondrites,
similar to carbonaceous chondrites (CV3). 相似文献
988.
以平衡级模型用块状三对角矩阵技术,对强极性的醋酸甲酯催化精馏水解过程进行模拟,在改变空速、水酯比、回流比等操作条件以及塔板数下,用模拟的酯水解率、塔内温度、水解液的酸水比与实验值进行了比较,结果令人满意 相似文献
989.
杭州湾北岸漕泾-柘林近岸海域浮游生物的调查 总被引:1,自引:0,他引:1
1996年11月和1997年3月,对漕泾-柘林的近岸海域的浮游生物进行了调查,1996年11月浮游植物平均密度为3.39×104个/L,密集于高潮带,主要有舟形藻、圆筛藻、直链藻等5种藻类,舟形藻为优势种;1997年3月平均密度为1.65×104个/L,密集于潮下带,主要有囊裸藻、针杆藻、小球藻等7种,囊裸藻为优势种.1996年11月,浮游动物的平均个体数为2.84×102个地,原生动物为优势种类;1997年3月,平均个体数为1.83×102个/L,以多毛类疣足幼虫为主;两次调查时浮游动物都密集于低潮带. 相似文献
990.
葛淼 《贵州大学学报(自然科学版)》1998,15(2):125-130
为制定中国健康中老年男性血沉参考值(温氏法)的统一标准提供科学依据,本文收集了中国各地测定的健康中老年男性血沉参考值(温氏法),并对其与地理因素的关系进行了研究,发现海拔高度是影响健康中老年男性血沉参考值(温氏法)最主要的因素,随着海拔高度的逐渐增大,健康中老年男性血沉参考值(温氏法)在逐渐的减小,相关性很显著.用逐步回归分析的方法推导出了一个回归方程,如果知道了中国某地的地理因素,变可以用这个回归方程估算这个地区的健康中老年男性血沉参考值(温氏法),依据健康中老年男性血沉参考值(温氏法)与地理因素的依赖关系把中国分为青藏区,西南区,西北区,东南区,华北区,东北区等六个区. 相似文献